Front sprocket gone/frame damage/rear sprocket shot!

Hi there KZ Rider Folks!

I previously posted in another thread, but was advised to start my own thread (perhaps) because its a bit of a unique situation. That being said, here's what I wrote in the previous thread! And some folks we very kind to comment, advise, etc.!

Hi there All,

My very first post - super stoked, but also super bummed. I have fallen in love with KZs and cannot wait to get going on this bike - everything is exciting, as I know very little about KZs.

So, I recently purchased my 1977 KZ1000 LTD and had my brother drive it home (as I live in Japan). On the way home the front sprocket fell off (at roughly 55mph) and locked up the rear wheel. Thankfully he's OK.

But the bike seems to be OK, save the frame (see pic). I had my good mechanic buddy check to see if the output shaft was bent/moved up and down - thankfully NO! A small amount of fore/aft movement, but nothing to be concerned about.

My concern lies with the frame/swing arm obviously, but also about the rear tire... it actually seems (via the pics) to be OK, but I am wondering is there anything you experts (saying this humbly) would caution against/offer advice on how to go about repairing this so I essentially do not have the problems again?

How should I go about button up the frame/swing arm?

I found this beautiful site, and will order the necessary parts soo, but want everyone's opinions and advice first please!!

www.z1enterprises.com/motorcycles/Kawasa...in-sprockets-z1.html

Also, I cannot seem to find a consensus on which sprocket sizes to go with - am I correct in researching/understanding that the stock sprockets are FRONT:15t REAR: 33t?

Sorry, I am new to all of this, but still super stoked to get crackin on this thing! Very much looking forward to the help!

Mucho thanks in advance!

Since the frame will likely be welded up next week (Monday) I have been agonizing over what sprocket and chain setup to get?? Should I just get the original 15f/33r (630) chain setup, or should I opt for the 530 setup??

Also, someone mentioned in another threat about (forgive me this is off the top of my head) going with a "bigger tooth setup" via a 18f/45r (530) setup to help with chain tension, etc.??

Again, I am new to all of this so any and all advice and explanations are greatly appreciated! And, for what it's worth, I intend on using the bike as a cruiser, and not a race or street fighter setup. I have plans of making it into a Mad Max like bike in the future, but for now I just want to ride my bike!

Here are some pictures of the bike, and damage!

I'm very happy with my 16/35 setup with the 630 O ring chain. Still great on takeoff, can drop to 2nd at 55 and grab a handfull. :woohoo: Good at HWY speed, not buzzy like the crotch rockets out there. I can drop to 2nd at speed and now they have to catch me. :whistle:
Steve

The chain has been running slack on the frame for quite a long time to cut through like that and it coming off has finished the job.
The tubing is 1/8" thick so you wouldn't get damage like that with a one time incident.
It hasn't really weakened the frame though and it's an easy fix by just welding a patch over it to close the holes.
2.2 to 1 is the stock final drive ratio and either 15/33 or 15/35 was the sprocket sizes used depending on model.
Sprocket sizes do nothing to affect chain tension and all that bigger one will do is bring the chain further away from the swingarm but closer to the frame rail.
Just use the same gearing you have if you are happy with it and pay close attention to chain adjustment and maintainence to avoid this happening again.

SWest wrote: I'm very happy with my 16/35 setup with the 630 O ring chain. Still great on takeoff, can drop to 2nd at 55 and grab a handfull. :woohoo: Good at HWY speed, not buzzy like the crotch rockets out there. I can drop to 2nd at speed and now they have to catch me. :whistle:
Steve

THANK YOU! This is precisely the information I was looking for. Is there really any need to switch over to a 530 setup?

zed1015 wrote: The chain has been running slack on the frame for quite a long time to cut through like that and it coming off has finished the job.
The tubing is 1/8" thick so you wouldn't get damage like that with a one time incident.
It hasn't really weakened the frame though and it's an easy fix by just welding a patch over it to close the holes.
2.2 to 1 is the stock final drive ratio and either 15/33 or 15/35 was the sprocket sizes used depending on model.
Sprocket sizes do nothing to affect chain tension and all that bigger one will do is bring the chain further away from the swingarm but closer to the frame rail.
Just use the same gearing you have if you are happy with it and pay close attention to chain adjustment and maintainence to avoid this happening again.

Thank you for the comment and advice, Zed! Duly noted on the the bigger sprockets and how it positions differently, but does not affect the tension.

I haven't owned anything but Harleys, so I do not have a preference when it comes to gearing yet, so as you folks suggested I am going to stick with the stock setup for now and get a feel for the "original" setup.

As far as the frame damage/repair goes, thank you guys for noting the chain had been riding on the frame like that for a while. I didn't notice that until just now - there's set of previous grooves besides the new ones that opened up. As far as repairs, my brother in law who owned a welding shop for 20+ yrs said it should really be a problem - clean it up, fill in the damaged portion, and put a patch/semi-sleeve over it (all TIG welded, of course).

Thank you all so much - haven't been this stoked on a purchase since my Trans Am (High School)!

Any other things/problem areas to advise the shop I take it to - ie: typical problematic issues with the KZs? Really hoping to ride this when I get home, and then add some things while I'm home for 2 weeks (Emgo headlight cowl, maybe 4 into 1 exhaust, etc.??).

Apart from general wear and tear, lack of maintenance or PO bodges there is no real problematic issues specific with these big Kwaks.
That's why we love 'em so much.
As for 530 chain conversions the 530 is just as strong as the 630 but slightly lighter and more common on newer machines so easier and cheaper to get a replacement at short notice.
The rear sprocket is the same 6 bolt pattern as most modern Kwak ZXR 750's ZX9's etc.
If making up your own kit then just look up JTR488 for the rear and choose your tooth count and the front is a 13 tooth small spline common on many Kwaks and Suzukis.

Yes, the original stock sprockets for the 1977 KZ1000LTD were FRONT:15t REAR: 33t. See link below for 1977 KZ1000-B1 (LTD) part numbers. Ed

www.kawasaki.com/Parts/PartsDiagrams/1977/KZ1000-B1

SWest wrote: I'm very happy with my 16/35 setup with the 630 O ring chain. Still great on takeoff, can drop to 2nd at 55 and grab a handfull. :woohoo: Good at HWY speed, not buzzy like the crotch rockets out there. I can drop to 2nd at speed and now they have to catch me. :whistle:
Steve

Just out of curiosity, what size chain (link) did you go with? 630-92?

Yes but some take 94.